CVE-2025-66622: matrix-sdk-base denial of service via custom m.room.join_rules event values
(updated )
The matrix-sdk-base crate is unable to handle responses that include custom m.room.join_rules values due to a serialization bug.
This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate’s sync process will stall, preventing further processing for all rooms.
References
- github.com/advisories/GHSA-jj6p-3m75-g2p3
- github.com/matrix-org/matrix-rust-sdk
- github.com/matrix-org/matrix-rust-sdk/commit/4ea0418abefab2aa93f8851a4d39c723e703e6b0
- github.com/matrix-org/matrix-rust-sdk/pull/5924
- github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-jj6p-3m75-g2p3
- nvd.nist.gov/vuln/detail/CVE-2025-66622
- rustsec.org/advisories/RUSTSEC-2025-0135.html
Code Behaviors & Features
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